Exponential ADC

[Tony Clark]

>  I want to get an Exponential ADC, ie an ADC that I can scale such that 1V
> increase doubles the value on the output. I would like 16Bit (24 bit would
> be superb!), 14 would be acceptable and I dont think 12bit would do.
> 
>   Short of using an Epoxnential convertor and then driving a normal ADC I
> wondered if anyone had any suggestions?
>   Are there any Exponential ADCs out there? if so where I cant find them.

   Um, don't you mean DAC?  I don't think I've ever seen an exponential 
A/D converter, but I know I've seen some exotic D/A converters.  Heck, 
you might be able to take one of the multiplying DACs and feed the output 
back into the scale input and get some form of exponential response.  
Might be cheaper too than buying a specialized one.

   Tony

------------------------------------,----------------------------------
I can't drive (my Moog) 55!         |     The E-Music DIY Archive
------------------------------------|  
Tony Clark -- clark at andrews.edu     | aupe.phys.andrews.edu/diy_archive
http://aupe.phys.andrews.edu/~clark |     Contributions welcomed!
------------------------------------'----------------------------------